This week, a swifter method of testing for coronavirus pioneered in South Korea began popping up in a few locations across the U.S. that could prove to be faster and safer for patients and medical providers. Patients showing the specific set of symptoms associated with Covid-19 are encouraged to drive to some medical center parking lots, where doctors will swab a cheek to test for the virus without patients ever having to leave their vehicles.

Colorado state government took the lead on the drive-thru strategy in that state. On Wednesday, doctors set up shop in the parking lot of Colorado Department of Public Health and Environment’s lab to offer tests to people who have authorization from their doctors.

To get a doctor’s order, patients must have a fever and signs of respiratory illness like shortness of breath. They also have to meet one additional criteria that places them in a high-risk group, such as being a resident of a retirement home, being a healthcare worker or first responder, having a history of travel to an affected area within the last 14 days, or living with a chronic medical condition. Testing is free and does not require proof of insurance.

“What we can say now is that testing as many people as possible through drive-through testing will help us isolate those who are ill, which will help provide protection to our vulnerable populations and assist with the public health response,” a representative for the Colorado Department of Public Health and Environment told Route Fifty over email.

Colorado had 45 confirmed cases of Covid-19, the disease caused by the new coronavirus, as of Thursday afternoon. The state tested 343 people.

Drive-thru testing ensures that people who are sick because of the coronavirus don’t infect others in a cramped hospital or doctor’s office setting. The system also allows doctors and nurses to limit their interaction with sick patients and care for larger numbers of them as quickly as possible.

The testing center in Colorado will see patients for four hours a day, and managed to swab 160 in the first day—though the state lab can only analyze about 80 samples a day, so some will be sent to private labs instead. The state currently has around 900 testing kits, but federal authorities have promised an additional 1,500 will be provided this week.

At a press conference on Wednesday, Colorado Gov. Jared Polis said the number of kits promised by federal authorities won’t be anywhere close to enough. “A proper containment effort will require thousands or tens of thousands of tests administered each day,” he said. “I’m really calling on the federal government and our private-sector partners to do everything they can to exponentially scale testing as immediately as we can to help us limit the spread effectively.”

By Thursday, wait times for the drive-thru testing center reached four hours, the Denver Post reported.

Dr. Nirav Shah, a senior scholar at Stanford University’s Clinical Excellence Research Center, said that conducting drive-thru testing is “absolutely the right approach” for hospitals and public health departments. “We want to keep people safe and minimize exposure,” he said. “Things like drive-thru testing, when done thoughtfully, keep patients from further contamination and ensure provider safety. But we need a more coordinated approach to this, instead of state-by-state or hospital-by-hospital.”

The CDC has not yet released any guidance for local governments and hospitals that want to try drive-thru testing, and did not respond to a request for comment as to when they might do so.

Shah, who previously served as commissioner of the New York Department of Health, said that creating clear protocols for drive-thrus wouldn’t be very hard. “There are principles of infection control, like changing gloves between patients, that we already do in the hospital,” he said. “We just need specific workflows in the parking lot to keep to the same standards. It’s a mindset shift, but we need to adhere to public health protocols no matter the setting.”

Stanford, which is now operating a drive-thru testing center, is uniquely well-prepared. In 2009, during the height of the H1N1 virus scare, Stanford Hospital became the first medical system in the U.S. to run a pandemic triage model using a drive-thru system.

But even hospitals that are well-prepared face the critical challenge of insufficient testing supplies. Lawmakers at a congressional hearing on Thursday expressed a growing frustration with the federal government’s response to the coronavirus, arguing that testing kits need to be produced and distributed much more quickly. Testing rates in the U.S. lag far behind other countries like South Korea, where drive-thru testing has become the go-to method.

"I don't think anyone is going to leave that briefing satisfied with what's going on with testing right now ... bottom line, you leave that briefing and we are not where we need to be and not sure when we are going to get there," Illinois Rep. Mike Quigley, a Democrat, told CNN. "We are flying blind."

At the hearing, Rep. Debbie Wasserman Schultz, a Democrat from Florida, expressed frustration that many people who wanted to be tested, such as health care workers, had been refused. "The system is not really geared to what we need right now," responded Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases. "That is a failing. Let's admit it."

Shah said that two things are critically important to improving testing right now: increasing the availability of test kits and shortening the timeline for results. “In the next two weeks, the availability of testing will increase exponentially as more labs are approved to test,” he said. “The turnaround time for a test at Stanford is currently 12 to 24 hours. We’ll need to make that much faster.”

Cleveland Clinic on Thursday announced that researchers will have developed a test that can produce results within eight hours by the end of the month. As testing advances, Shah said not to be alarmed by the resulting numbers. “In the next week, we’ll see a large increase in cases, not because the disease is spreading more rapidly, but because we’re finally catching up to the backlog of people who haven’t been tested,” he said.